• Journal of the Korean Institute of Landscape Architecture
• /
• v.21 no.1
• /
• pp.125-137
• /
• 1993

Ansan urban nature park is 197.8ha and located in Seodeamun-Gu of Seoul. Flora of Ansan consisted of 141 species, 76 genera, 40 families in woody plants. This study was conducted to analyze the natural environment and establish the park management plan with ecological approach. The result of this study is summarized as follows. 1. The short term plan shall be performed in six vegetation management zones; Robinia pseudoacacia community zone, Sorbus alnifolia community zone, Quercus acutissima community zone, Populus ${\times}$albagrandulosa community zone, Pinus densiflora community zone, and landscape planting zone. Pinus densiflora and landscape planting zones shall be managed artificially, the others managed with ecological approach. 2. The long term plan shall be performed in four vegetation management zones; Robinia pseudoacacia community zone, Quercus spp. community zone, Pinus densiflora community zone, and landscape planting zone. Pinus densiflora and landscape planting zones shall be managed artificially, the others managed with ecological approach. 3. Because soil of Ansan is acidified and the soil disturbed growth of plants, the improvement of soil is necessary. The fertilization shall be performed in three zones; evergreen confierous tree zone(ex. P. densiflora), Quercus spp. zone, and the other deciduous tree zone(ex. R. pseudoacacia).

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.558-564
• /
• 2006

When vehicles pass the connection between the bridge and earthwork, the difference of both sections' stiffness produces an increasing wheelload. As a consequence, it results in the excessive vibration of vehicles and the damage of bearing system. In general, steel plate girder railway bridges without ballast track have larger stiffness than the bridge with ballast, and produces larger impulse on the bridge superstructure. Thus, it is necessary to reduce the differences of both stiffness. This study presents parametric studies on the behavior of plate girder bridges and their tracks by means of various stiffnesses and the length of approach zone. The results of numerical study showed that the smaller the stiffness of both sides and the longer the length of approach zone, the variation of wheelload becomes smaller. Hence, it gives less burden into the plate girder bridges and their tracks. It is expected that the results of parametric study can be used as a preliminary data for the determination of economical length on the approach zone and the stiffness of both sides.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.4 no.2
• /
• pp.113-129
• /
• 2000

This study evaluates the behavior and strength of an anchorage zone of the prestressed concrete box girder bridge on the Kyungboo highway railroad using the 2D SUB-3D STM approach and a linear elastic finite element analysis. The 2D SUB-3D STM approach utilizes several two-dimensional sub strut-tie models that represent the compressive and tensile stress flows of each projected plane of the three-dimensional structural concrete in the selection of a three dimensional strut-tie model, evaluation of the effective strengths of the concrete struts, and verification of the geometric compatibility condition and bearing capacity of the critical nodal zones in the selected three-dimensional strut-tie model. The finite element analysis uses an 8-node brick element and the longitudinal prestressing force is considered as the equivalent nodal force. Analysis results show that the 2D SUB-3D STM approach and linear elastic finite element method can be effectively applied to the analysis and design of three-dimensional structural concrete including a prestressed concrete box girder anchorage zone.

• Journal of the Korean Academy of Esthetic Dentistry
• /
• v.16 no.2
• /
• pp.19-20
• /
• 2007

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37 no.6B
• /
• pp.443-452
• /
• 2012

In Mobile Ad-hoc Networks, previous routing protocols classified into proactive and reactive approach respectively have pros and cons under the use of applications and environment. Moreover, to integrate their advantages in case by case, hybrid approach is consistently researched, and Zone Routing Protocol (ZRP) was motivating many recent hybrid protocols. ZRP uses proactive routing to the node located within the zone defined by the specific number of hops, while it uses reactive routing to other nodes. However, in ZRP, because proactive routing is applied only within the zone defined by the number of hops, the zone is formed regardless of whether real data communication occurred frequently or not. In this paper, we propose a new hybrid routing scheme which employs the zone method but forms customized zone considering traffic load and number of hops, by a new decision method named Dynamic Zone Decision (DZD). Additionally, we analyze the performance of the proposed scheme, comparing with the previous proactive, reactive, and hybrid routings.

• Journal of the Korean Society of Combustion
• /
• v.6 no.2
• /
• pp.36-42
• /
• 2001

Usually, we use the flame thickness and turbulence scale to classify the flame structure on a phase diagram of turbulent combustion. The flame structure in turbulence is still in debate, and many studies have been done. Since the flame motion is rapid and its reaction zone thickness is very thin, it is difficult to estimate the flame thickness. Here, we propose a new approach to determine the reaction zone thickness based on ion current signals obtained by an electrostatic probe, which has enough time and space resolution to detect flame fluctuation. Since the signal depends on the flow condition and flame curvature, it may be difficult to analyze directly these signals and examine the flame characteristics. However, ion concentration is high only in the region where hydrocarbon-oxygen reactions occur, and we can specify the reaction zone. Based on the reaction zone existing, we estimate the reaction zone thickness. We obtain the thickness of flames both in the cyclone-jet combustor and on a Bunsen burner, compared with theoretically predicted value, the Zeldovich thickness. Results show that the experimentally obtained thickness is almost the same as the Zeldovich thickness. It is concluded that this approach can be used to obtain the local flame structure for modeling turbulent combustion.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.9 no.3
• /
• pp.146-155
• /
• 2006

A handful of previous studies have attempted to integrate socioeconomic data and remotely sensed data for urban quality of life assessment with their spatial dimension in a zonal unit. However, such a zone-based approach not only has the unrealistic assumption that all attributes of a zone are uniformly spatially distributed throughout the zone, but also has resulted in serious methodological difficulties such as the modifiable areal unit problem and the incompatibility problem with environmental data. An alternative to the zone-based approach can be a pixel-based approach which gets its spatial dimension through a pixel. This paper proposes a pixel-based approach to linking remotely sensed data with socioeconomic data in GIS for urban quality of life assessment. The pixel-based approach uses dasymetric mapping and spatial interpolation to spatially disaggregate socioeconomic data and integrates remotely sensed data with spatially disaggregated socioeconomic data for the quality of life assessment. This approach was implemented and compared with a zone-based approach using a case study of Fulton County, Georgia. Results indicate that the pixel-based approach allows for the calculation of a microscale indicator in the urban quality of life assessment and facilitates efficient data integration and visualization in the assessment although it costs an intermediate step with more processing time such as the disaggregation of zonal data. The results also demonstrate that the pixel-based approach opens up the potential for the development of new database and increased analytical capabilities in urban analysis.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.13 no.4
• /
• pp.215-223
• /
• 2018

Recently, as interest of wearable devices has increased, commercially available smart wristbands and applications have been used as a tool for personal healthy management. However most previous studies have focused on evaluating the accuracy and reliability of the technical problems of wearable devices, especially step counts, walking distance, and energy consumption measured from the smart wristbands. In this study, we propose a physical activity evaluation model using classification rules, induced from the associative classification mining approach. These rules associated with five physical activities were generated by considering activities and walking times in target heart rate zones such as 'Out-of Zone', 'Fat Burn Zone', 'Cardio Zone', and 'Peak Zone'. In the experiment, we evaluated the prediction power of classification rules and verified its effectiveness by comparing classification accuracies between the proposed model and support vector machine.

• Journal of the Korean Solar Energy Society
• /
• v.30 no.2
• /
• pp.33-38
• /
• 2010

The perimeter zone is space which receives a significant effect of ambient condition, it is necessary to improve the thermal performance in order to building energy saving. For this reason, a lot of study about the active approach is being performed, such as perimeter-less air conditioning system. But the performance of the perimeter zone is necessary to improve, through the passive approach. Therefore, the purpose of this study is to provide basic materials of energy-saving design of perimeter zone, based of the PAL that simulation changing the thickness of insulation and the rate of windows.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.5 no.4
• /
• pp.384-394
• /
• 1993

A simple surf zone model is presented The present model takes a quite different approach by showing that wave action is conserved in the surf zone. This condition together with the conservation of energy enables us to develop a surf zone model that requires fewer empirical coefficients. The model is capable of predicting surf zone properties and is presented in analytical forms for the two-dimensional gradually-sloped bottoms. The analytical results were compared favorably with available laboratory data. This surf zone model provides the surface current pattern of the vertical circulation model. and consequently, significantly contributes to solving the three-dimensional current pattern.